Question: William ate 4 slices of pizza. Omar ate 1 slice. If William ate $\dfrac{4}{7}$ of the pizza, what fraction of the pizza was eaten?
Solution: If 4 slices represent $\dfrac{4}{7}$ of the pizza, there must have been a total of 7 slices. $\text{fraction of pizza eaten} = \dfrac{\text{number of slices eaten}}{\text{number of slices total}}$ They ate ${5}$ out of $7$ slices. They ate $\dfrac{5}{7}$ of the pizza.